Method of purifying cotton-seed-hull fiber.



F. W. STOCKTON.

METHOD 0F PURIFYING COTTON SEED HULL FIBER.

APPLICATION man JUNE 13. 191i.

Patented Feb. 1S, 1919.

@man stars man@ te FRANK W. STOCKTON, 0F PITTSBURGH, l:PENN'SYLVANIA, ASSIGNOR TO EAST ST. LOUIS COTTON OIL COMPANY, OF ILLINOIS.

NATIONAL STOCK YARDS, ILLINOIS, .A CORPORATION OF METHOD OF PURIFYING COTTON-SEED-HULL FIBER.

. ratentea reel. is, isis.

Application filed September 13, 1917. Serial No. 191.246.

This invention relates to the purifying of cotton-seed hull fiber, and includes a novel method of purifying such fiber.

After the cotton is removed from the cottonseed by ginning, most of the remaining shorter fibers are removed by what is known as the delinting operation, somewhat similar to that of gunning, the shorter fiber thus removed in the delinting process being called linters. After the delinting process there nevertheless remains on'the cottonseed a small amount of a kind of fiber or fuzz which is not removed by the delinting process and which is usually made up of immature cotton fiber, averaging about three-sixteenths of an` inch in length. In order to obtain this short fiber from the seeds, the hulls are separated from the meats, as by the usualhulling or decortieating process, and the separated hulls are passed through an attrition mill consisting essentially of two steel disks facing and almost touching each ther and running in opposite directions and having grooves in their faces. Whenthe cottonseed hulls are fed through the center of one of these disks to the narrow space between the disks, they are subjected to high speed attrition and the fiber is thereby cut off from the hulls and the hulls incidentally ground up. The ber and ground hulls escape from the periphery of the disks and are discharged to a separator, which separates the fiber from the ground hull.

The cottonseed hull fiber thus obtained contains usually about twenty-five per cent. of the cottonseed hull in the form of fine particles or flakes, and with practically all the fibers attached to these fine flakes.

The present invention relates to the purification of the crude fiber thus admiXed with and attached to the fine scales or particles; and has for its primary object the purification of such fiber and the separation and removal therefrom of the scales and hull particles.

The purification process of my invention comprises a boiling of the impure fiber and associated hull particles in dilute alkaline liquor to soften the hull particles so that they may be more readily disintegrated, or otherwise softening the hull particles; after which the impure fiber thus treated is subjected 1o a rolling operation to disintegrate and mash the softened hull particles; and the fiber is then separated from the disintegrated and separated hull particles by a special washing operation.

In the carrying out of the first step of the process, I have found it ofv advantage to boil the fiber in alkaline water containing, for example, about four per cent. of caustic soda for about five hours. Such alkaline liquor has no injurious effect upon the fibers themselves, but it attacks the hull particles more especially and softens them so that they can be disintegrated.

This softening of the hull particles may also be accomplished by suitable treatment with solutions of substances other than al- .kalis and even with water alone. The boiling operation may be conducted under pressure, as 1n an autoclave. The softening may valso be effected by fermentation or by enzym f action.

After the fibers and their associated hull particles have been treated, and the hull particles have been thus softened, the material is passed several times between powerful steel rolls for the purpose of mashing the hull particles without seriously mashing the fiber. Inasmuch as the hull particles are much thicker than the fiber, and also are softer, it is easy to effect this mashing operation, byproper adjustment of the rolls, Without serious injury to the fiber. By this rolling operation most of the fiber is detached from the yhull particles, and the hull particles are extremely nely disintegrated. This disintegration may extend, to some extent, even to the ultimate constituent cells..

After the mashing operation, the mashed mass of fiber and hull is treated for `the removal of the very fine particles of hull from the fiber. I have found it of particular adratus illustrated, more or less conventionally and diagrammatically, in the accompanying drawing; in which:

Figure 1- is a top View of the apparatus with parts' removed; and

4teeth thereon. This drum is arranged above an elevated portion 4 of 0the tank which has corresponding or complementary teeth 5, between which and the teeth on the drum 6 the liquor and contents of the tank are circulated and agitated. The arrangement of these teeth is also such that they lbeat up and separate the ber and ne hull particles and form them into a suspension 1n the water contained in the tank. The drum 6 may be driven in any suitable manner, as by the pulley 7.

On the opposite side of the central partition, and near the other end of the tank, is

3o a revolving screen 8, suitably mountedand' supported and driven by means of the pulley 9. The bearing at the end of this screen v is hollow as indicated at 10, and has extending therethrough the outlet pipe -11and the inlet pipe'13. "The pipe r11 has its inner end extending downwardly at 12 and has its outer end connected to a` pump, (not shown),

' for pumping the water from the tank after outside of the screen;

v it haspassed through'the screen. yThe pipe 40 13 terminates in a series of spray nozzles indicatedat 14, and arranged to spray water through the. screen from the inside and thereby remove adhering particles from the The spray nozzles are arranged above the level of the water -in the tank 'so that the material removed thereby will flow back in the tank.l Suitable guards 15 and 16 are shown covering the lrotary screen and` the rotary drum, respectively.

In the operation of the apparatus described, the mashed ber and associated hull particles are put into the machine which is lled with water to Lthe proper level. As

thematerial passes between the drum 6 and the water through the pipe 11 are inopera# tion, the water will be drawnI through the screen and will lbe removed from within the screen through the pipe 11, carrying with it the ne suspended hull particles,

which are of a neness permitting rthem freely to pass through the screen. 4 The ber, because of its length, is held on the outside of the screen and is washed olf by the spray 14 and returned to the tank. In practice,

the rotary screen is revolvedslowly, while,

the rotary drum 6 is rotated at high speed lto give the desired agitation and beating up' and separation of the ber and hull particles. o c

. By continuing the o eration in the manner described for a su icient period of time, for example, for an hour and a half, the ber can be substantially freed from the hull particles. I have found that it is easy in this" way to treat cottonseed hull ber originally containing about twenty-ve per cent. of hull particles and to reduce the amount of such particles to about one .per cent. or even less. At the end of the purication process, the puried ber is removed from the tank, as by a draw-oil opening (not shown) and se arated from the accompanying water by ltration, or transferred to a space ofl storage for further treatment. Where dry ber is desired, the water can be removed by ltering and by drying, as' will readily made by well known methods. This nal puricationwill depend upon the use to which the ber is to be put'; and may consist of a further boiling with lye, followed by bleaching. with chlorin or hypochlorite. Also, the ber may be treated with benzin or other suitable solvent', to remove the fatty or waxy matter, etc.; or this extraction process may take place in conjunction with other purification processes or before or after such other treatment. The improved process of my invention makes unnecessary any elaborate subsequent purication and gives a product which can readily be treated.

after a further nal purication where this is necessary, for nitrating or other purposes.

The process of the present invention is not intended for the treatment ofcrushed cottonseed hulls for the preliminary separation ofthe hull and ber. Such a prelminary separation of the hull and ber is usually effected after the crushed hulls have been passed through an attrition mill, as hereinbefore described. The process of the present invention is intended for the purication of the crude cottonseed hull ber 'obtained as a result of such a preliminary separation of the hull and ber, as herein described. Bythe expression cottonseed hull ber in thevappended claims is therefore meant the crude ber obtained from the crushed cottonseed hulls, and containing about twenty-ve per cent. of the cottonseed hull. This crude cottonseed hull ber is thus principally composed of cotton ber, and such hull as it contains is in the fo-rm of ne particles or flakes.

I claim 1. The method of purifying cottonseed hull ber and of separating the ber from associated hulll particles, which comprises softening the hull particles, mashing the material to disintegrate the softened hull particles and detach the liber therefrom, and subjecting the mashed material to a cleaning operation and thereby washing the ne hull parjices from the ber, substantially as descri e 2. The method of purifying cottonseed hull ber and of separating the ber from associated hull particles, which comprises softening theA hull particles by treatment with dilute alkaline liquor, mashing the material to disintegrate the softened hull particles and detach the ber therefrom, and subjecting the mashed material to a cleaning operation and thereby washing the ne hull particles from the ber, substantially as described.

3. The method of purifying cottonseed hull ber and of separating the ber from associated hull particles, which comprises softening the hull particles, passing the material between rollers and thereby mashing and disintegrating the hull particles and separating the ber therefrom, and subjecting the mashed material to a cleaning operation and thereby washing the ne hull particles from the ber, substantially as described. j

4. The method of purifying cottonseed hull ber and of separating the ber from associated hull particles, which comprises softening the hull particles, meshing the material to disintegrate the softened hull parparticles and to form a suspension thereof in the water, and ltering off the water and ne hull particles from the ber, substantially as described.

5. The method of purifying cottonseed hull ber and of separating the softened hull particles therefrom, which comprises mashing the material to disintegrate the hull particles and separate the ber therefrom, subjecting the resulting material, in admiXture with water, to a beating operation and thereby separating the ber and hull particles and forming a suspension thereof in the water, subjecting the suspension to a progressive ltering operation and thereby ltering and removing the water and nely suspended p. rticles of hull from the ber, adding fresh amounts of water and continuing the beating and ltering operation until the ber has been puried from the hull particles, substantially as described.

6. The method of purifying cottonseed hull ber and of separating the hull particles therefrom, which comprises boiling the ber in alkaline water containing about four per cent. of caustic alkali for about ve hours to soften the hull particles, passing the boiled ber between rolls and thereby mashing and disintegrating the hull particles, and subjecting the mashed material to a cleaning operation and thereby separating the ne, disintegrated hull particles from the' ber, substantially as described.

ln testimony whereof l aflix my signature.

FRANK W. STOCKTON. 

